European freight yard operations vs US Operations

Good for you.

I noticed both of those, but I don't know how to correct a Wiki article so I left 'em be.

~Pete

Reply to
Twibil
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On 9/1/2009 4:57 PM Twibil spake thus:

Q: How do you correct a Wikipedia article? A: Sorry, that's impossible.

[not a riddle or a joke]
Reply to
David Nebenzahl

The Garrat is effectively a 'tank locomotive' whereas the US Mallets, (excluding the Triplex) are 'tender locomotives'. The same problem of reducing tractive effort occurs with almost every tank locomotive ever in operation. Simply moving the boiler/engine unit pivots outwards and placing the supplies in a seperate tender would solve that "problem". The Triplex Mallet had the same problem, but in that case it really would have been a problem as all the loss of weight was from just one engine unit.

Regards, Greg.P.

Reply to
Greg.Procter

Well, no, had circumstances differed, the triplex *might* have demonstrated that problem eventually, but since the inadequate boiler never could supply enough steam for sustained running anyway, that difficulty rarely -if ever- arose.

Reply to
Twibil

That's not correct! Britain used loose link couplers on goods wagons. (from c1800 to c1960)

3 links. Sometime about 1920 a variation which used ao open T shaped link which was flipped after coupling to reduce the loose slack. Smooth train operation depended on journal friction and the Brake Van at the rear of the train to keep the train stretched. Small goods locos (0-6-0) could haul relatively heavy trains at slow speeds because such a train could be reversed to eliminate the slack and then got moving one wagon at a time. Of course they were limited on gradients, but Britain is relatively flat. European goods trains had screw couplers from 1858. The screw link was thrown over the center coupler hook and then the screw link was tightened until the opposing buffers were gently compressed. The coupling and buffer springs were then in compression tension against each other. The advantage is that shock loads are greatly reduced. Offsetting this is the fact that the entire train runs as a single unit. IMO this is a major reason why European goods trains are generally short and therefore run at higher speeds.

US trains still need the brake hoses coupling manually. The shunting assistant might as well couple the wagons while he is there! ;-)

Regards, Greg.P.

Reply to
Greg.Procter

I've already covered that. And the "T" shaped coupler was called the "Instanter", already covered that aswell.

We've covered all of that as well.

And all that.

And that.

Reply to
Roger T.

A good point. However, the power trains (engines) would always be more or less well balanced, which is a great deal more than could be be said for some Mallets which were woefully ill balanced. I think that I am correct in saying one or two were very nearly unusable because of that and had to be modified or abandoned. My memory is rather shaky here. Perhaps someone else can shed further light on the aspect of well balanced Mallets, or otherwise.

Oh! I just happened to thumb through a copy of Train Shed Encyclopedia to check a point and, referring to an earlier comment I made, I note the Allegheny H8's were designed for 60 mph max. and 30-35 max. continuous power output. Why then run them for long periods, or any other locomotive, at crawling speed - it just doesn't make sense

Reply to
Brian Bailey

A few years back I was watching a few wagons being coupled to the train I was riding on. The guy was standing right inside the buffers as the extra wagons approached - with no way to get out quickly... This may be forbidden, but I'd rather see center couplers than such a procedure!

So, in this case I do appreciate any country with center couplers installed throughout the system! No matter whether the brake lines need manual coupling...

Apart from that, especially freight trains are quite often not coupled as closely with the screw-couplers as they should be, nor are passenger trains... So there still is the possibility to "reverse" the engine and compress the train, so as to start the train a wagon at a time - even if it's less than with a very loose coupler. Actually, if the engine crew does it right while stopping the train, they have the train already compressed when starting.

But most freight trains I do see are quite short (five locos with 12 wagons!) or mostly empty (10 container on ~20 wagons), so this ain't necessary anyway.

In the end, it's not always "black and white" as in "good and bad", but mostly some shade of "gray" - screw-type couplers have some advantages over center couplers and vice versa... Both the American as well as the European systems have derailments, trains "loosing" wagons, whatever... Neither system uses a fully automatic coupler...

Actually I do think, a fully automatic coupler might simply not work well - imagine some attachment to the normal coupler that connects the brake lines and opens the valve once the lines connect. If a wagon separated from the train, the valves would close and the separate wagon would continue rolling for quite a time without braking! So either there is some built-in failsafe safeguard or this ain't possible? Probably it would be sufficient to delay closing the valves after separation for a second or two? Again, very gray ;-)

This - in a much smaller scale - is a point on a model railroad - badly aligned couplers and train separation... To my shame I must admit I do have a few such cars...

Ciao...

Reply to
Bernhard Agthe

One thing to remember is that American practice diverged strongly from European practice very quickly. Europeans did short trains with small power till just recently and thus didn't need the American style couplers that would allow rapid assembly of trains of long length. Thus the European need for air braking systems and so forth weren't as needed. For a reference of how far the two systems had diverged, go look at the testing done on the Karuss-Maffei locos destined for the DRG and SP in the '60s. Very interesting story.

-- Bob May

rmay at nethere.com http: slash /nav.to slash bobmay http: slash /bobmay dot astronomy.net

Reply to
Bob May

Back when the USRA designs were done, there wasn't much interest in really high speed for freight trains - cars had friction bearings on the axles as well as the locos - so the need for a good balancing of the drivers really hadn't become critical. It wasn't later till some of the western roads wanted to get their trains over the track faster that the latest techniques weree applied to dynamically balance freight haulers.

-- Bob May

rmay at nethere.com http: slash /nav.to slash bobmay http: slash /bobmay dot astronomy.net

Reply to
Bob May

Bernhard Agthe wrote: [...]

Existing air brakes systems are fail safe:

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HTH wolf k.

Reply to
Wolf K

Whatever the boiler's failings, assuming it could raise enough pressure to slip the drivers on starting, the major change in weight on the tender driving wheels would have created traction problems with that group. If I remember rightly, the main frame drivers cylinders feed the two outer pairs of cylinders in compound form. If the rear driver set lacked weight then either those drivers would slip, causing a drop in the mid pressure receiver, which would effectively drop steam pressure to the front engine unit and raise pressure to the main engine unit, or the maximum throttle and cut-off would have to be kept below the rear engine's traction limit.

Regards, Greg.P.

Reply to
Greg.Procter

OK, haven't kept up with this thread - however, I started my post to correct incorrect information being posted.

Regards, Greg.P.

Reply to
Greg.Procter

YYes, that is a scary proceedure!

The trade-off is rougher riding and more damage to freight. A worker or two written off every year against a high number of damage claims? ;-(

Any time there's a spring there's compression available, but a properly tightened Euro train doesn't have the 10cm slack between each wagon of the historic British train nor even the 1/4" to 1/2" slack of the US cars. Loose slack is different to sprung slack as far as damage to contents is concerned. The unloved Euro automatic center coupler was still going to have circa 1mm slack and increased damage claims were a considerable concern.

I used "black and white" phraseology as adding all the greys increases the text by a factor of 10 or so ;-)

Not sure whether the Euro center coupler addressed that or not. It was to be automatic in connecting all functions. Broken brake lines should have been simple enough to detect - there's two great big couplers connected or not! Looks to me as though the whole scheme got too expensive to complete, so they failed to start.

Reply to
Greg.Procter

All European trains have and had air braking for the last 150 odd years.

Reply to
Greg.Procter

I think you are wrong. Most British trains were vacuum braked until relatively recent (40 odd years) times.

That is assuming you include Britain as par of the European continent.

Reply to
Mike Hughes

Britain part of the European Continent? Absolutely not - for most of the period that railways have existed, Europe was isolated from Britain by the English Channel, or by La Manche from the French point of view. As such European and British railways developed separately. Other parts of Europe also used vacuum brakes, but if they wanted to run wagons outside their own systems they had either to add parallel airbrakes or convert. Through air brake piping was the absolute minimum.

Regards, Greg.P.

Reply to
Greg.Procter

On 9/2/2009 7:04 PM Mike Hughes spake thus:

Isn't vacuum braking a form of air braking? (Uses air, after all.)

Reply to
David Nebenzahl

It's more a "no air" system. Like IBM and Apple, both personal computers operating on binary code, but ...

Regards, Greg.P.

Reply to
Greg.Procter

I thought most Brits still do not consider themselves Euros, regardless of the EU. I know they didn't when I lived there. :-)

Reply to
Roger T.

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